Vehicle miles of travel (VMT) are key data for highway planning and management, and a common measure of roadway use. Along with other data, VMT are often used in estimating congestion, air quality, and potential gas-tax revenues, and can provide a general measure of the level of the nation's economic activity.

Vehicle Miles Traveled

Aug-04

Aug-05

Highway miles (millions)

262,133

262,514

Percent change from same month previous year

0.75

0.15

NOTE: The current value is compared to the value from the same month in the previous year to account for seasonality.

SOURCE: U.S. Department of Transportation, Federal Highway Administration, available at http://www.fhwa.dot.gov/, as of October 2005.